Android 片段类中的TimePickerDialog
我可以实现吗Android 片段类中的TimePickerDialog,android,classcastexception,timepicker,Android,Classcastexception,Timepicker,我可以实现吗 TimePickerDialog.OnTimeSetListener 在片段类中? 如果可能的话,怎么做? 这是我的TimePickerFragment.class public class TimePickerFragment extends DialogFragment { @NonNull @Override public Dialog onCreateDialog(Bundle savedInstanceState) { Calendar c = Calen
TimePickerDialog.OnTimeSetListener
在片段类中?
如果可能的话,怎么做?
这是我的TimePickerFragment.class
public class TimePickerFragment extends DialogFragment {
@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
Calendar c = Calendar.getInstance();
int cHour = c.get(Calendar.HOUR_OF_DAY);
int cMinute = c.get(Calendar.MINUTE);
return new TimePickerDialog(getActivity(), (TimePickerDialog.OnTimeSetListener) getActivity(), cHour, cMinute, android.text.format.DateFormat.is24HourFormat(getActivity()));
}
}
我是否需要修改此代码以便在片段类中使用它
这就是我想要实现它的地方
public class BluetoothFragment extends Fragment
我已经试过了
但我得到了这个错误
java.lang.ClassCastException: com.example.android.bluetoothplantdroid.MainActivity cannot be cast to android.app.TimePickerDialog$OnTimeSetListener
您可以将侦听器设置为DialogFragment,以在源代码片段中获取回调
public class TimePickerFragment extends DialogFragment {
public static TimePickerFragment newInstance() {
return new TimePickerFragment();
}
private TimePickerDialog.OnTimeSetListener listener;
@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
Calendar c = Calendar.getInstance();
int cHour = c.get(Calendar.HOUR_OF_DAY);
int cMinute = c.get(Calendar.MINUTE);
return new TimePickerDialog(getActivity(), listener, cHour, cMinute,
android.text.format.DateFormat.is24HourFormat(getActivity()));
}
public void setListener(TimePickerDialog.OnTimeSetListener listener) {
this.listener = listener;
}
}
这就是如何在originfragment中获得回调-
public class MyFragment extends Fragment implements TimePickerDialog.OnTimeSetListener {
May be click event of some widget... {
TimePickerFragment.newInstance().setListener(this);
// Show your dialog
}
@Override
public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
// data when time has been set.
}
}
请遵循以下代码:
传递活动或片段上下文
public static void setTimeFromTimePicker(Context context, EditText editText) {
int hourOfDay, minute;
final Calendar c = Calendar.getInstance();
hourOfDay = c.get(Calendar.HOUR_OF_DAY);
minute = c.get(Calendar.MINUTE);
TimePickerDialog dpd = new TimePickerDialog(context, (timePicker, hourOfDay1, minute1) -> {
Time time = new Time(hourOfDay1, minute1, 0);
SimpleDateFormat simpleDateFormat = new
SimpleDateFormat("hh:mm aa", Locale.getDefault());
String s = simpleDateFormat.format(time);
editText.setText(s);
}, hourOfDay, minute, false);
dpd.show();
}
警告:如果您的应用程序支持低于3.0的Android版本,请确保调用getSupportFragmentManager()以获取FragmentManager实例。另外,请确保显示时间选择器的活动扩展了FragmentActivity,而不是标准的activity类。首先在此类中创建一个构造函数,我认为您要设置文本,因此创建上述类的构造函数,并将context和textview作为参数传递,现在,在片段中创建这个类的对象,并在
setListener(this)中传递您的上下文和textview可能重复的this
代码>是上下文侦听器还是事件侦听器?它是侦听器
。因此,您的片段将实现TimePickerDialog.OnTimeSetListener
,当选择时间时,您将在onTimeSet
上获取数据。
import android.app.Dialog;
import android.app.DialogFragment;
import android.app.Fragment;
import android.app.TimePickerDialog;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TimePicker;
import java.util.Calendar;
/**
* A simple {@link Fragment} subclass.
*/
public class TimePickerFragment extends DialogFragment implements TimePickerDialog.OnTimeSetListener {
public TimePickerFragment() {
// Required empty public constructor
}
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Use the current time as the default values for the picker
final Calendar calendar = Calendar.getInstance();
int hour = calendar.get(Calendar.HOUR_OF_DAY);
int minute = calendar.get(Calendar.MINUTE);
// Create a new instance of TimePickerDialog and return it
return new TimePickerDialog(getActivity(), this, hour, minute,
DateFormat.is24HourFormat(getActivity()));
}
public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
// Do something with the time chosen by the user
}
}